Demountable sheave



Jan. 24, 1950 D. 1.. KEssLER 2,495,459

DEMOUNTABLE SHEAVE Filed June 19, 1948 mmvrox. DAV/D lam 6H A ess/crPatented Jan. 24, 1950 DEMOUNTABLE SHEAVE David Lowell Kessler, Denver,0010., assignor to {Gates Rubber Company, Denver, 0010., a corpo- Vration of Colorado Application June 19, 1948, Serial No. 34,070

3Claims. '(Cl. 74-230.01)

This invention relates to improvements in sheaves, more particularlytosheaves of the multiple groove type employed in connection with multipleV-belt power transmissions, but'is not limited to such use.

It is the object of this invention to produce a sheave assembly of atwo-part construction, comprising a hub andarim assembly of suchconstruction that 'the same rim may be com bined with hubs-bored for thereception'of shafts of different sizes and in which rims of difierentdiameters may be combined with'thesame'hub.

Another object is to produce a sheave of such construction that the hubcan be clamped to' the shaft by means of the: rim so that torquegfromthe shaft can be transmitted through thesheave without'the necessityofsplines or keys between the shaft and the hub.

Another object is toproduce a=sheave assembly of such construction thatit can be easily and quickly attached to and removed from a shaft.

A further object is to provide a sheave assembly of such, constructionthat the rim portion may be positioned on the hub in two longitudinallydifferent positions.

A still further object is to provide a sheave assembly of suchconstruction thatthe rim may be removed from the hub while the latter isin position on the shaft so that rims of different sizes may be quicklysubstituted.

The above and other objects that may appear as the description proceedsare attained by means of a construction and an arrangement of parts thatwill now be described in detail, and for this purpose reference will behad tothe accompanying drawing in which the invention has beenillustrated, and in which:

Figure l is a diametrical section through a sheave assembly, taken online Il, Figure 2;

Figure 2 is a side elevation of the sheave looking towards theleft inFigure 1;

Figure 3 is a sectiontaken on 1ine.33, Figure 4;

Figure 4 is a side elevation looking towards the left in Figure 3; and

Figure 5 is a partial section similar to that shown in Figure 1 andshowshow a run like shown in Figure 3 can be employed with the hub toeffect additional longitudinal adjustment.

Referring now to the drawing, reference numeral l5 designates the hubwhich has an axial opening of any desired size and which is providedwith an outwardly extending flange It. Inclined or outwardly taperedsurfaces I! and I1 extend from opposite sides of the flange as shown inFigure 1. Thehub and the flange are separated by means of a diametricalsaw cut i8 which extends from a point approximately at the innerdiameter of flange 16 on *oneside to the outside and entirely throughthe flange on the a tapered opening of somewhat smaller diameter thanthe normal diameter of inclined surfaces l7 and H so that when web 22 isin the position shown in Figure 1 and forced againstflangelB by means ofthe cap screws 20, thehub will be;

contracted slightly so as to force the inner -surface of the openingtherein into frictional engagement with a shaft. Of course it isunderstood that the opening in the'hub must be of such a diameter thatthe hub can:be-s1id onto the shaft with an easy sliding fit and after ithas been properly positioned on the shaft, the hub and rim assembly canthen be clamped frictionally to the shaft by tightening the cap screwsso as to bring the opposing surfaces of the flange and web intoengagement.

Referring now to Figures 1 and 2, it will be observed that flange 16 isnearer one end of the hub than the other. In this specific embodiment,the inclined surface 11 isof thesamewidth as the thickness of web 22 sothat when the parts are in assembled and operative position, the end ofthe hub will be in the same plane as the outer surface of web .22. 7When the two parts are assembled as shown in Figure 1, the sheave willproject a short distance beyond the-outer end of the hub. However, ifthe rim is reversed so as to bring it onto the inclined surface H, thetwo parts will still retain substantially the same longitudinal relationas shown in Figure 1. It is to be understood that rim 2| may have eithera greater or a lesser nurnber of groovesthan those shown and ittherefore becomes a great -corrvenience to be able to reverse the partsin the manner made possible due to thedoubleinclined or conical surfaces[1 and J1.

In Figures 3 and 4 a slightly modified form of construction has beenshown. The hub has been designated by reference numeral I5a and isprovided with an outwardly extending flange 16a. A frustoconical orinclined surface l'la extends outwardly from the outer surface of flangeIlia. Rim Zla has been shown as having five grooves instead of four asin Figures 1 and 2 and web 22a is somewhat thicker than web 22 and hasthe wall of its opening provided with two outwardly flaring taperedsurfaces 23. Web 22a is provided with six holes. Those designated byreference numeral 24 are for the reception of cap screws 25. threaded,but have no corresponding holes in flange [6a. When the sheave assemblyshown in Figures 3 and 4 is applied, the rim is positioned either asshown in Figure 3, or it may be reversed; in the latter case it willextend inwardly beyond the inner surface of the hub. Such arrangementsare sometimes necessary in connection with certain machinery. After thehub has been positioned on the shaft, screws 25 are tightened, forcingweb 22a upwardly along the inclined surface Ila, thereby contracting thehub about the shaft forcing the same into frictional engagement with theshaft. Due to the small taper and to the fact that the cap screws, whenproperly tightened, will exert a strong force, the hub is contractedabove the shaft with suflicient force to form a frictional engagementthat will prevent accidental rotation in the absence of keys or splines.

It will be observed that in both forms of the invention shown, flangesi6 and ifia and webs 22 and 22a are positioned to one side of the middlepoint of each part. This makes it possible to obtain variouslongitudinal adjustments that are very useful in effecting the properpositioning of the sheaves to bring them into alignment with cooperatingsheaves on spaced parallel axes. When the rim is to be removed, forexample, if it is to be replaced by one of a greater diameter, thesecuring bolts are removed and two of them are positioned in thethreaded holes 28 and moved inwardly towards the surface of flange I6a,thereby producing a force tending to move the web outwardly and effect arelease between the two parts.

It is pointed out that the rim shown in Figures 3 and can be used withthe hub illustrated in Figure 1, whereby a variety of adjustments may beeffected. In the same manner the rim shown in Figure 1 can be used withthe hub shown in Figures 8 and 5. Figure 5 shows how a rim having aflange 22a with oppositely inclined frustoconical surfaces can besubstituted for the one shown in Figure 1 so as to effect additionaladiustments in the manner explained in connection with Figures 3 and 4.

With the hub illustrated in Figure 3, two adjustments may be made, oneof said adjustments is the one illustrated and the other involvesturning the rim in the opposite direction.

With the hub shown in Figure 5 and the rim shown in Figures 3 and 5 fordifferent adjustments may be made, two on each side of the flange.

Having described the invention what is claimed as new is:

1. In a demountable sheave of the power transmission type, comprising ahub having an axial opening for the reception of a shaft, a flangesurrounding the hub in a plane perpendicular to its axis, there being anoutwardly tapering The holes designated by numerals 26 are.

frusto-conical surface on each side of the flange, the flange beingpositioned nearer one end of the hub than the other, the hub and flangehaving a radial saw kerf, a rim having an inwardly extending flangeprovided with a central opening, the wall of said opening having twooutwardly flaring surfaces of the same taper as the tapers of thefrusto-conioal surface on the hub, the diameters of the openings in theflange of the rim being slightly smaller than the corresponding outsidediameter of the hub, whereby the opening in the hub will be reduced whenthe I rim is in position and forced towards the flange on the hub, theflange being nearer one end of the rim than the other, whereby the huband flange may be assembled in any one of four different relativelongitudinal positions.

2. In a demountable sheave of the power transmission type, comprising ahub having an axial opening for the reception of a shaft, a flangesurrounding the hub in a plane perpendicular to the hub axis, the hubhaving an outwardly tapering irusto-conical surface on one side of theflange, the hub and flange having a radial saw kerf, a rim having aninwardly extending flange provided with a central opening, the openingwall comprising two outwardly flaring frustoconical surfaces of the sametaper as the frustoconical surfaces on the hub, but of slightly smallerradii, whereby when the rim is positioned on the hub with one of itstapered surfaces in engagement with the outwardly tapered surface of thehub and forced inwardly towards the flange, the opening in the hub willdecrease in diameter, the inwardly extending flange on the rim beingspaced nearer one end than the other, whereby the hub and rim may beassembled in two different relative longitudinal positions by reversingthe rim relative to the hub,

3. In a demountable sheave of the power transmission type, comprising ahub member having an axial opening for the reception of a shaft, a rimhaving an inwardly extending flange member adapted to axially telescopeover the hub member, one of said members having a pair of frusto-conicalsurfaces extending in opposite directions from a plane therebetweennormal to the hub axis, the surfaces intersecting at said plane, atleast one frusto-conical surface on the other member engageable with oneof said pair of frusto-conical surfaces, a flange surrounding the hub,the last named flange and the hub having a slot therein to permitcontraction of the hub on a shaft, and means for drawing said inwardlyextending flange member toward the last named flange to secure the rimto the hub and contract the hub on a shaft.

DAVID LOWELL KESSLER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,580,919 Reeves Apr. 13, 19262,269,821 Kemphert et a1. Jan. 13, 1942

